The Prices To The Other Tribes Are, At Araya Ten, At Cumana Twelve Reals.) This Augmentation Of Price Is Slightly Compensated By Greater Purity Of The Salt, And By The Facility With Which The Fishermen And Farmers Can Procure It In Abundance During The Whole Year.

The salt-works of Araya yielded to the treasury, in 1799, a clear income of eight thousand piastres.

Considered as a branch of industry the salt produced here is not of any great importance, but the nature of the soil which contains the salt-marshes is well worthy of attention. In order to obtain a clear idea of the geological connection existing between this muriatiferous soil and the rocks of more ancient formation, we shall take a general view of the neighbouring mountains of Cumana, and those of the peninsula of Araya, and the island of Margareta.

Three great parallel chains extend from east to west. The two most northerly chains are primitive, and contain the mica-slates of Macanao, and the San Juan Valley, of Maniquarez, and of Chuparipari. These we shall distinguish by the names of Cordillera of the island of Margareta, and Cordillera of Araya. The third chain, the most southerly of the whole, the Cordillera of the Brigantine and of the Cocollar, contains rocks only of secondary formation; and, what is remarkable enough, though analogous to the geological constitution of the Alps westward of St. Gothard, the primitive chain is much less elevated than that which was composed of secondary rocks.* (* In New Andalusia, the Cordillera of the Cocollar nowhere contains primitive rocks. If these rocks form the nucleus of this chain, and rise above the level of the neighbouring plains, which is scarcely probable, we must suppose that they are all covered with limestone and sandstone. In the Swiss Alps, on the contrary, the chain which is designated under the too vague denomination of lateral and calcareous, contains primitive rocks, which, according to the observations of Escher and Leopold von Buch, are often visible to the height of eight hundred or a thousand toises.) The sea has separated the two northern Cordilleras, those of the island of Margareta and the peninsula of Araya; and the small islands of Coche and of Cubagua are remnants of the land that was submerged. Farther to the south, the vast gulf Cariaco stretches away, like a longitudinal valley formed by the irruption of the sea, between the two small chains of Araya and the Cocollar, between the mica-slate and the Alpine limestone. We shall soon see that the direction of the strata, very regular in the first of these rocks, is not quite parallel with the general direction of the gulf. In the high Alps of Europe, the great longitudinal valley of the Rhone also sometimes cuts at an oblique angle the calcareous banks in which it has been excavated.

The two parallel chains of Araya and the Cocollar were connected, to the east of the town of Cariaco, between the lakes of Campoma and Putaquao, by a kind of transverse dyke, which bears the name of Cerro de Meapire, and which in distant times, by resisting the impulse of the waves, has hindered the waters of the gulf of Cariaco from uniting with those of the gulf of Paria. Thus, in Switzerland, the central chain, that which passes by the Col de Ferrex, the Simplon, St. Gothard, and the Splugen, is connected on the north and the south with two lateral chains, by the mountains of Furca and Maloya. It is interesting to recall to mind those striking analogies exhibited in both continents by the external structure of the globe.

The primitive chain of Araya ends abruptly in the meridian of the village of Maniquarez; and the western slope of the peninsula, as well as the plains in the midst of which stands the castle of San Antonio, is covered with very recent formations of sandstone and clay mixed with gypsum. Near Maniquarez, breccia or sandstone with calcareous cement, which might easily be confounded with real limestone, lies immediately over the mica-slate; while on the opposite side, near Punta Delgada, this sandstone covers a compact bluish grey limestone, almost destitute of petrifactions, and traversed by small veins of calcareous spar. This last rock is analogous to the limestone of the high Alps.* (* Alpenkalkstein.)

The very recent sandstone formation of the peninsula of Araya contains: - first, near Punta Arenas, a stratified sandstone, composed of very fine grains, united by a calcareous cement in small quantity; - secondly, at the Cerro de la Vela, a schistose sandstone,* (* Sandsteinschiefer.) without mica, and passing into slate-clay,* (* Thonschiefer.) which accompanies coal; - thirdly, on the western side, between Punta Gorda and the ruins of the castle of Santiago, breccia composed of petrified sea-shells united by a calcareous cement, in which are mingled grains of quartz; - fourthly, near the point of Barigon, whence the stone employed for building at Cumana is obtained, banks of yellowish white shelly limestone, in which are found some scattered grains of quartz; - fifthly, at Penas Negras, at the top of the Cerro de la Vela, a bluish grey compact limestone, very tender, almost without petrifactions, and covering the schistose sandstone. However extraordinary this mixture of sandstone and compact limestone* (* Dichter kalkstein.) may appear, we cannot doubt that these strata belong to one and the same formation. The very recent secondary rocks everywhere present analogous phenomena; the molasse of the Pays de Vaud contains a fetid shelly limestone, and the cerite limestone of the banks of the Seine is sometimes mixed with sandstone.

The strata of calcareous breccia are composed of an infinite number of sea-shells, from four to six inches in diameter, and in part well preserved. We find they contain not ammonites, but ampullaires, solens, and terebratulae. The greater part of these shells are mixed: the oysters and pectinites being sometimes arranged in families. The whole are easily detached, and their interior is filled with fossil madrepores and cellepores.

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